Unable to upload picture from Android to java server

Question

I've been trying to implement profile photo upload feature by Android Retrofit + SpringMVC. Java server unable to respond Retrofit API call. Related code snippet is given below:

ApiInterface

@Multipart
@POST("user/profileImage")
Call<ResponseBody> uploadImage(@Part MultipartBody.Part image, @Part("name") RequestBody name);

uploadToServer

public void uploadToServer(){
    //Get retrofit client
    Retrofit retrofit = ApiClient.getClient();
    //Get API interface
    ApiInterface apiInterface = retrofit.create(ApiInterface.class);
    // Get image parts
    MultipartBody.Part imageParts = bitmapToMultipart(imageBitmap);
    //Get image name
    RequestBody name = RequestBody.create(MediaType.parse("text/plain"), "ProfileImage");
    //Call image upload API
    Call<ResponseBody> call = apiInterface.uploadImage(imageParts,name);
    call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
            ResponseBody body = response.body();
        }

        @Override
        public void onFailure(Call<ResponseBody> call, Throwable t) {
            t.printStackTrace();
        }
    });
}

bitmapToMultipart

public MultipartBody.Part bitmapToMultipart(Bitmap imageBitmap){
    File file = null;
    try {
        //create a file to write bitmap data
        file = new File(this.getCacheDir(), "imageBitmap");
        file.createNewFile();

        //Convert bitmap to byte array
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        imageBitmap.compress(Bitmap.CompressFormat.JPEG, 0 /*ignored for PNG*/, bos);
        byte[] bitmapdata = bos.toByteArray();

        //write the bytes in file
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(bitmapdata);
        fos.flush();
        fos.close();
    }catch(IOException e){
        e.printStackTrace();
    }
    RequestBody reqFile = RequestBody.create(MediaType.parse("image/*"), file);
    MultipartBody.Part body = MultipartBody.Part.createFormData("upload", file.getName(), reqFile);

    return body;
}

Java SpringMVC controller

@Controller
@RequestMapping("/user")
public class UserController{
    @RequestMapping(value = "/profileImage", method = RequestMethod.POST)
    public  @ResponseBody String imageUploader(@RequestParam("image") MultipartFile image, @RequestBody RequestBody name)throws Exception{
        return "";
    }
}

Problem is: Request not even reaching to java server.

Answer 1

In your uploadToServer() function media type should be "multipart/form-data" in place of "text/plain" for field name...

//Get image name
    RequestBody name = RequestBody.create(MediaType.parse("multipart/form-data"), "ProfileImage");

In your bitmapToMultipart() function media type should be "multipart/form-data". ("image/*" should also work but if not "multipart/form-data" will definitely work)

refer - How to Upload Image file in Retrofit 2

And in your spring controller you should use @RequestParam in place of @Requestbody

@Controller
@RequestMapping("/user")
public class UserController{
    @RequestMapping(value = "/profileImage", method = RequestMethod.POST)
    public  @ResponseBody String imageUploader(@RequestParam("image") MultipartFile image, @RequestParam String name)throws Exception{
        return "";
    }
}